The hotly contested election for mayor of London this week sparked accusations of inappropriate attempts to canvass Jewish votes.

The Jewish Labour Movement has complained to the Zionist Federation for sending out an email circular which publicised Conservative challenger Boris Johnson’s visit to North-West London last Sunday.

In another incident on the same day, Nicky Gavron, the Labour deputy mayor, drew protests for plugging Ken Livingstone’s bid for re-election at a Holocaust play in the West End.

JLM treasurer Lawrie Nerva said: “We are concerned that the ZF should be seen to be supporting a particular party. They’ve shown themselves to be partisan in giving publicity to one side.”

The email gave advance notice of a Conservative Friends of Israel-organised visit by Mr Johnson to “the heart of Jewish North London”.

But Gavin Gross, the ZF’s director of public affairs, rejected claims of political intervention. “The ZF hasn’t supported a candidate in the mayoral election and we won’t be endorsing any candidate. Nowhere did our email say that the ZF supports Boris Johnson or encourage people to vote for him.

“We merely gave people information about an event aimed at the Jewish community in North London, clearly labelled as being organised by the Conservative Friends of Israel. As members of the ZF email list know, we regularly publicise events that we think might be interesting from other organisations.”

Ms Gavron, who is contesting the Barnet and Camden seat for Labour in the London Assembly elections, was speaking after a performance of And Then They Came for Me, based on the experiences of Holocaust survivor Eva Schloss, at the Criterion Theatre.

She had been invited by its producer Nic Careem to talk about her own mother’s story as a refugee from Nazi Germany.

But when she mentioned voting for Ken Livingstone, the audience reacted negatively, according to one of its Jewish members, Lance Anisfeld. “The audience found somewhat distasteful her opportunistic public plea to vote for Ken Livingstone in the forthcoming mayoral elections, and ‘tutted’ her down,” he said. “There’s a time and place for campaigning and this was certainly not it.”

Mr Careem, who himself is Muslim, also told the JC that he had found the electoral reference “inappropriate”.

But Ms Gavron, who is Ken Livingstone’s deputy, said: “It was never my intention to upset anyone at what was an inspiring event. I was asked to speak in a personal capacity because Ken Livingstone was unable to attend. I was asked to speak about my own experiences as the daughter of a Holocaust survivor and about the BNP.

“My main purpose was to urge people to go and vote on May 1 because a low turnout plays into the hands of the far-right British National Party.”

She added: “Since I am Ken’s deputy and a Labour Party candidate, it would have been odd if I didn’t recommend voting Labour. I understand that people can disagree with me on that point — but I am absolutely sure that every one who heard me did understand my key message: you’ve got to use all your votes to stop the BNP.”

Meanwhile, the Muslim Association of Britain — which was involved in the visit of the controversial cleric, Sheikh Yussuf Al-Qaradawi, to the UK four years ago — has urged supporters to back Mr Livingstone’s campaign with Green candidate Sian Berry as second preference.